Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: John Antle. Includes bibliographical references (leaves 70-74).

Thesis (Ph. D.)--University of Kentucky, 1993. / Vita. Includes bibliographical references (leaves 143-149).

Thesis (doctoral)--Humboldt-University, Berlin, 2004.

Thèse complémentaire--Université de Paris. / "Notice bibliographique": p. [129]-132.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The consumption of fresh produce has increased over the past few decades, but it has also resulted in an increase in foodborne outbreaks. Once fresh produce gets contaminated, microbes can survive or even multiply on the produce. There is, however, very little information available on what impact environmental conditions will have on the survival and growth of potential pathogens. Thus the purpose of the first phase of the study was to determine the impact of different environmental factors: carbon levels; temperature; incubation time; and initial microbial load on the growth of E.coli and other "indigenous" microbes present in the Plankenburg river water. Water from the Plankenburg River was incubated at 10° to 35°C and the E.coli and aerobic (ACC) loads determined at 0, 6, 12 and 24 h. The impact of different COD:N:P ratios on growth were also evaluated by altering the water values. It was found that in non-sterile river water the E.coli levels increased with increase in incubation temperature. Minimal growth took place between 10° and 20°C and the largest growth increases at 35°C. The data showed that E.coli dieoff was rapid when the nutrient levels were low. It was concluded that the carbon (COD) level is a major growth limiting factor in river water. The impact of adjusted carbon levels on the growth of E.coli present was then evaluated. The E.coli was found to die-off faster at the higher temperatures when the carbon levels were low (COD = <10 mg.L-1), possibly due to nutrient limitations. At higher carbon levels (COD = >100 mg.L-1), the growth profiles of E.coli showed major growth increases with no die-off during the 24 h period, probably because of the availability of sufficient nutrient levels. Even though standard methods can be used to identify if irrigation water is faecally contaminated it is important to confirm that organisms on fresh produce are from the faecally polluted irrigation water. The purpose of the second study was to determine the effect of daily irrigation on carry-over, the effect of “once-off” irrigation on the survival of E.coli on the produce, identifying types of E.coli in the irrigation water and those on irrigated fresh produce, and then linking the E.coli types. In the first trial, green beans planted in a tunnel and irrigated on a daily basis (14 days) with Plankenburg water and a “pure wild-type” E.coli at a concentration of 106 cfu.mL-1 were evaluated. The results showed that E.coli is carried over from irrigation water to the irrigated green beans, especially when the E.coli levels in the river water were high. After the enumeration steps, colonies from both the irrigation water and from the irrigated beans were selected (67 isolates from the green beans and 72 from the irrigation water). Unique phenotypic (API) profiles were generated for each isolate. The first indication of linking was confirmed based on the degree of phenotypic similarity using numerical clustering systems. The results showed that these isolates were related and originated from the same pollution source. The use of PCR further confirmed (uidA positive) that all the phenotypically identified strains were E.coli. With multiplex PCR, further linking confirmation was shown when strains tested positive for the mdh gene. The presence of EPEC strains in the irrigation water was also revealed. Thirteen E.coli isolates, which showed positive carry-over links between the irrigation water and the green beans, were further analysed using triplex PCR. However, no direct phylogenetic link to the three main phenotypic E.coli clusters was found. However the triplex PCR could be of value in identifying the source of faecal pollution. For further linking confirmation, DNA sequencing was done on selected phenotypically clustered strains. The oriC-locus sequencing was unsuccessful in distinguishing between the different E.coli strains while the dnaJ sequences showed clear differences and similarities between E.coli strains and some E.cloacae and K.pneumoniae strains respectively from the river water and from the beans. The probability of faecal coliforms being carried-over from irrigation water to fresh produce was shown. This showed the importance of a "multi-method" approach to confirm carryover. / AFRIKAANSE OPSOMMING: Tydens die afgelope paar dekades het die verbruik van vars groente en vrugte vermeerder, maar dit het ook gepaard gegaan met ‘n toename in voedselverwante uitbrekings. Indien vars groente of vrugte gekontamineer word, kan die mikrobes daarop oorleef en ook vermeerder. Daar is min informasie beskikbaar oor die impak van omgewingskondisies op die oorlewing en groei van potensiële patogene. Dus was die doel van die eerste fase van die studie om die impak van verskillende omgewingsfaktore te bepaal: koolstofvlakke; temperatuur; inkubasietyd; en aanvanklike mikrobiese lading op die groei van E.coli en ander “inheemse” mikrobes wat teenwoordig is in die Plankenburg Rivier water. Water van die Plankenburg Rivier was geïnkubeer by 10° tot 35°C en die E.coli en aërobe kolonie tellings (AKT) was bepaal by 0, 6, 12 en 24 h. Die impak van verskeie CSB:S:F verhoudings op groei, was ook geëvalueer deur die waarders van die rivierwater te verander. Dit was gevind dat in die nie-steriele rivierwater, die E.coli vlakke vermeerder het soos die inkubasie temperatuur vermeerder het. Minimale groei het plaasgevind by 10° en 20°C en die meeste groei by 35°C. Die data het gewys dat die E.coli vinnig afgesterwe het as die nutriënt vlakke laag was. Die gevolgtrekking was dat die koolstofvlakke (CSB) die hoof faktor is wat die groei beperk in rivierwater. Die impak van die aangepasde koolstofvlakke op die groei van E.coli teenwoordig was ook geevalueer. Daar was gevind dat die E.coli vinniger afsterf by die hoër temperature as die koolstofvlakke laag is (CSB = <10 mg.L-1), omdat die nutriente moontlik beperk is. Tydens die hoë koolstofvlakke (CSB = >100 mg.L-1), het die E.coli groeiprofiele baie groei getoon met geen afsterwe tydens die 24 h periode nie, omrede dat daar moontlik genoeg nutriente beskikbaar was. Al kan standaard metodes gebruik word om fekale kontaminasie in besproeiingswater te identifiseer, is dit belangrik om te kan bevestig of die organismes op vars groente of vrugte van fekale gekontamineerde besproeiingswater is. Die doel van die tweede fase van die studie was om die effek van daaglikse besproeiing op oordrag te bepaal, effek van eenkeer se besproeiing op die oorleweing van E.coli op groenboontjies, identifisering van E.coli tipes in die besproeiingswater en op die groenboontjies, asook die koppeling van E.coli tipes. In die eerste proef was groenboontjies geplant in ‘n tonnel en daagliks besproei (14 dae) met Plankenburg water en ‘n “suiwer wilde-tipe” E.coli met ‘n konsentrasie van 106 cfu.mL-1. Die resultate het getoon dat E.coli oorgedra was van die besproeiingswater na die besproeide groenboontjies, veral toe die E.coli vlakke in die rivierwater hoog was. Na al die isoleringsstappe, is kolonies van die besproeiingswater en van die besproeide groenboontjies geselekteer (67 isolate van die groenboontjies en 72 van die besproeiingswater). Unieke fenotipiese (API) profiele was gegenereer vir elke isolaat. Die eerste indikasie van koppeling was bewys deur die graad van soortgelyke fenotipiese profiele deur numeriese groepering. Die resultate het gewys die isolate was verwant en oorspronklik van dieselfde bron van kontaminasie. Die gebruik van PKR het verder bewys (uidA positief) dat al die fenotipiese geidentifiseerde isolate E.coli was. Verdere koppeling was geidentifiseer met die multiplex PKR deurdat die isolate positief getoets het vir die mdh geen. Die teenwoordigheid van die EPEC isolate in die besproeiingswater was ook gevind. Dertien E.coli isolate, wat positiewe oordrag verbinding getoon het tussen die besproeiingswater en die groenboontjies, was verder geanaliseer deur triplex PKR. Geen direkte fenotipiese verbinding met die drie hoof fenotipiese E.coli groepe was egter gevind nie. Die triplex PKR kan wel van waarde wees om die bron van die fekale besoedeling te identifiseer. Vir verdere koppeling bevestiging, was DNA volgorde gedoen op isolate van geselekteerde fenotipiese groepe. Die oriC-locus volgorde was onsuksesvol om te onderskei tussen die verskillende E.coli tipes, terwyl die dnaJ volgordes duidelike verskille en ooreenstemmings getoon het tussen die E.coli asook party E.cloacae en K.pneumoniae tipes, onderskeidelik van die rivierwater en boontjies. Die waarskynlikheid van oordrag van fekale kolvorme vanaf besproeiingswater na vars goedere was getoon. Dit wys die belangrikheid van ‘n “multi-metode” benadering om oordrag te bewys.

Submitted by (edna.saturno@ufrpe.br) on 2016-06-10T11:12:31Z No. of bitstreams: 1 Vanessa Priscila Mamed Ali.pdf: 3876677 bytes, checksum: 624534c0b7f0189367b6335d2ec4229a (MD5) / Made available in DSpace on 2016-06-10T11:12:31Z (GMT). No. of bitstreams: 1 Vanessa Priscila Mamed Ali.pdf: 3876677 bytes, checksum: 624534c0b7f0189367b6335d2ec4229a (MD5) Previous issue date: 2013-06-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The objective of this research was to identify the statuos of the organization and hygiene problems found in the free markets of Afogados, Casa Amarela, Cordeiro e São José, in the city of Recife-PE. The methodologies adopted which supported this research were: questionnaires for consumers and merchants, in the field research, interviews with managers of trade bodies and government agencies, research bibliographic and photographic record. Such research has identified organizational problems regarding standardization of stalls / booths, difficult access and flow, human organ neglect sanitary supervision both in the handling of products, as environmental hygiene. They also identified the non periodicity of garbage collection causing bad smell due to perishable food. It was also observed that the fairs do not meet the requirements established by Csurb, and that most researched fairs are in a state of complete abandon. The results are presented through tables, graphs and pictures, which show the need for a revision to the rules of organization of fairs and training courses to promote the vendors regarding food handling, maintain by the government to collect garbage and inspection of fairs. / O objetivo desta pesquisa foi identificar aspectos organizacionais e de qualidade dos processos de comercialização de produtos hortifrutícolas bem como analisar algumas características dos atores da demanda e da oferta nas principais feiras livres associadas aos mercados públicos do Recife. As metodologias adotadas que subsidiaram esta pesquisa foram: aplicação de questionários para consumidores e feirantes, em pesquisa de campo, entrevista com orgãos gestores das feiras e orgãos públicos, pesquisa bibliografica envolvendo a revisão de dissertações, jornais, revistas, artigos e registro fotográfico. A referida pesquisa identificou problemas de organização em relação a padronização das bancas/barracas, dificuldade de acesso e de fluxo humano, o descaso de orgãos sanitários na fiscalização tanto da manipulação dos produtos, quanto da higienização do ambiente. Também foi identificada a não periodicidade da coleta de lixo causando mau cheiro devido a pericividade dos alimentos. Observou-se ainda, que as feiras não cumprem as exigências estabelecidas pela Csurb, e que a maior parte das feiras pesquisadas estão em estado de completo abandono. Os resultados são apresentados por meio de tabelas, gráficos e imagens, que apontam a necessidade de uma revisão para as regras de organização das feiras livres bem como promover cursos de capacitação para os feirantes referente a manipulação de alimentos, manter por parte do governo a coleta de lixo e a fiscalização das feiras livres.

A few vertically integrated retail chains increasingly dominate South Africa’s agro-food supply chain. M+M Planet Retail (2004) placed the market concentration among retailers to be as high as 96% for the top four chains leaving only 4% to the small competitors. The onset of this trend has led to the demise of a large number of “mom and pop” general dealers in favour of the sleek new stores as they were either priced or bought out of business. Players in the fresh produce market have proved to be resilient to this onslaught. The green grocers and hawkers have survived the “category killers” and appear to be able to face this competition head on. It is this resilience that is of interest to this study. The review of literature revealed a dearth of studies and hence methodology into the nature of the interaction between the three forms of retail. A preliminary survey also revealed the lack of coherent and detailed information, particularly among the greengrocers and hawkers. Thus the established methods of modelling competition analysis, namely the Structure Conduct Performance and the New Empirical Industrial Organisation frameworks, were deemed inappropriate. The study therefore took an exploratory form that relied on measures of central tendency and the perceptions of leading industry practitioners to reveal the nature and magnitude of competition between supermarkets, green grocers and hawkers. The study primarily drew on ‘Porter’s forces’ competition model to structure the investigation. It also employed a chain analysis approach including supply and value chain analysis (VCA) tools to analyse this competition. The study therefore sought to unpack the retail sections of the three chains in terms of identifying role-players; their relationships and interaction; as well as to account for the relative values that different types of fresh produce retailers generated for the final consumer. Besides the contribution to the general body of knowledge about the nature of the system that feeds us, this study provides means for the competing channels to upgrade and improve efficiency. A developmental and empowerment point of view was emphasised in the research, as such, identifying possible measures to upgrade and improve the informal sector was given precedence. The objective was to describe and analyse the competitive environment in which FFV was retailed in the Tshwane through a determination of the competitive and strategic behaviour of retailers and a mapping the flow of value. It was hypothesised that fresh produce retailers competed by varying elements of their marketing mix to suit their niche markets. The investigation was conducted in two phases; a pilot study followed by a survey involving a six-step sampling frame targeting a total of 120 respondents including 15 supermarkets, 30 greengrocers and 75 hawkers. This analysis was limited to the bounds of the Tshwane metropolitan area, South Africa, and focused on six fresh fruits and vegetable lines concurrently traded by supermarkets, greengrocers and hawkers. The main findings of the investigation include that tri-dimensional FFV retail competition was most intense in the middle-income areas of the city. The low income areas were dominated by informal traders while the large supermarkets chains and the large format greengrocers dominated the high income areas. The non-syndicated greengrocers were confined to the middle-income areas where competition was most intense. When the marketing strategies and chain maps were compared it was concluded that the tridimensional competitive environment was facilitated by the existence of multiple niches; the equalising effect of produce market based pricing; the general upgrade in product quality offered by all retailers; characteristics of fresh produce itself as compared to other foodstuffs and the existence of multiple market niches in the sector. Concluding the study were recommendations to improve (upgrade) the marketing performance of each of the three channels. / Dissertation (MSc(Agric) (Agricultural Economics))--University of Pretoria, 2007. / Agricultural Economics, Extension and Rural Development / MSc(Agric) / unrestricted

Please read the abstract in the section 00front of this document / Thesis (DCom (Financial Management))--University of Pretoria, 2006. / Financial Management / unrestricted